1. Field of the Invention
The present invention relates to pattern measurement methods and pattern measurement equipment and, in particular, to methods and equipment for measuring patterns in an image produced by a charged particle beam apparatus.
2. Description of the Related Art
A general manufacturing process of a semiconductor integrated circuit employs pattern measurement using a charged particle beam apparatus such as a scanning electron microscope. Recently, the use of design data (also referred to as computer aided design (CAD) data for convenience, below) of patterns has become common in such measurement.
Japanese Patent Application Publication No. 2002-328015 (corresponding to U.S. Pat. No. 7,026,615) discloses a technique for creating a template for pattern matching on the basis of CAD data, and thereby performing a matching process on the template based on the CAD data and a scanning electron microscope (SEM) image. Japanese Patent Application Publication No. 2007-079982 (corresponding to US 2007/0092129) discloses a pattern matching technique using a contour line segment group extracted from CAD data.
Japanese Patent Application Publication Nos. 2001-338304 (corresponding to U.S. Pat. No. 6,868,175), 2002-031525 (corresponding to US 2002/0015518) and 2006-234588 (corresponding to US 2006/0193508) disclose techniques for detecting and comparing edges of an inspected pattern and a datum pattern, and thereby detecting a shift amount of the inspected pattern with respect to its design data.